Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond annotations (readOnlyHint, idempotentHint, etc.), description discloses partial failure behavior, Bundlephobia's first measurement delay (5-30s), and lists sources_failed will indicate timeouts. No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Single paragraph but well-structured with purpose first, then details, then limitations. No wasted sentences. Could be slightly more concise but effective.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no output schema, description thoroughly explains return structure (summary block, per-advisory detail, links, alternatives) and covers edge cases like delays and fallbacks. Rich annotations complement the description.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with descriptions for both parameters. Description adds context: package accepts scoped packages, version defaults to latest, and explains return fields. Provides meaningful addition beyond schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states the tool performs a composite check for npm packages, combining deps.dev and bundlephobia. It distinguishes from other tools by specifying npm-only scope and explicitly mentioning what it returns (summary block, advisories, links, alternatives).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides explicit when-to-use guidance: 'whenever an agent asks is X safe / popular / small' and states that for PyPI/Maven/etc. users should use deps.dev directly. This clearly differentiates usage from alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.